1. Field of the Invention
The present invention concerns a static cooling electric chain saw. It also deals with the method implemented to achieve this static cooling.
More precisely, the invention applies to chain saws in which the drive of the cutting chain is performed by an electric motor.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98.
The drive of the cutting chain of the known electric chain saw is performed by means of low performance electric motors, so that about 50% of the power delivered by the motor is to be dissipated, to avoid the effect of overheating, because of the significant thermal losses generated.
The devices used to carry out the dissipation of the heat generated by the electric motor employ turbines or ventilators creating air circulation around the motor. The addition of a turbine or a ventilator to the motor of the saw has the considerable inconvenience of complicating the manufacture of the tool, increasing its production cost, and causing additional energy consumption, and adding to what is necessary to driving the cutting chain.
Furthermore, to be efficient, these cooling systems require openings to be made in the motor housing to facilitate the circulation of cooling air around the motor. The main inconvenience of these openings is to disrupt the sealing of the motor and to allow the penetration of water, dust and sawdust resulting from wood cutting wood operations.
In the document US-2005/0236917, an electric hand tool is described which includes an electric motor enclosed in a casing which is itself embedded in the tool housing, and a cooling system constituted by a thermal conducting device connecting said casing to said housing, so as to allow the heat produced by the motor to dissipate. This cooling device complicates the manufacture of the tool and does not allow for efficient heat dissipation for high-powered electric motors like those, which generally equip electric chain saws.
The particular aim of the invention is to remedy the aforementioned inconveniences of electric chain saws and their cooling system.